1. Field of the Invention
The present invention is related to a metered dispensing pump device preventable of water permeation. The device can be used on various bottles for suction and dispensing of liquid therein. The present invention is especially related to an improved metered dispensing pump device for liquid suction from a bottle loaded with hand washing cream, hair shampoo or shower gel etc. used for bathing. The liquid in the bottle can be protected from permeation and pollution of showering water by the device. And the stability and quality of the chemical liquid in the bottle can thus be well kept.
2. Description of the Prior Art
As is well known, a bottle loaded with normal chemical liquid such as hand washing cream, hair shampoo or shower gel etc. mostly is equipped with a metered dispensing pump device to allow a user to press it for suction of quantitative chemical liquid. Such a bottle loaded with normal chemical liquid such as hand washing cream, hair shampoo or shower gel etc. normally is placed in a watery environment such as in a bath room, especially at the spot under a shower for a user to conveniently press and obtain the chemical liquid for washing hair or body. However, the conventional metered dispensing pump device (as shown in FIG. 1) mounted on the bottle loaded with normal cleaning liquid placed in the watery environment is not water proofing, and water can often permeate into the bottle to influence quality of the chemical liquid.
In the conventional metered dispensing pump device shown in FIG. 1 as an example, when a user presses a liquid discharging knob 1, a piston 22 in a liquid storing pipe 2 full of the liquid is pressed down to approach a pipe-like seat 4 to make the liquid in the liquid storing pipe 2 push away a steel bead 21. Thereby, the liquid is discharged out of the bottle 10 through the liquid discharging knob 1, and an object of taking the liquid in a simple way can be obtained. And by elastic stretching and compressing of a spring 23, the piston 22 and the pipe 2 are pushed upwardly to provide suction, air can get through an air way 33 formed between a wall in a groove 31 of a cap 3 and the liquid storing pipe 2 and through a positioning annulus 32 to release the vacuum state in the bottle 10. Thereby, the liquid in the bottle 10 can propitiously push away a steel bead 41 on a liquid supplying pipe 42 to recharge the pipe 2.
Nevertheless, the above stated conventional metered dispensing pump device can have its groove 31 for receiving the liquid discharging knob 1 been accumulated with bathing water when in showering. When the liquid discharging knob 1 is pressed down, the bathing water accumulated in the groove 31 will get through the positioning annulus 32 and the airway 33 into the bottle 10. This pollutes the liquid in the bottle 10 and makes water therein diluted, makes microbe therein propagate to decay or deteriorate the liquid. These troubles come mainly from the air way 33 formed between the wall in the groove 31 of the cap 3 and the liquid storing pipe 2 and opening downward into the bottle 10 (as shown in FIG. 1). Therefore, it is the motive of the present invention to thoroughly solve these problems.